Sue Waters at The Edublogger is encouraging people to share their three favorite Web 2.0 tools. She’s begun a series of posts where she’s including suggestions.
In my comment there I nominated Edublogs (because it’s so easy to use and not blocked by our School District filters), VoiceThread (because you can do so many things with it) and Mozy (an automatic web-based back-up system for the files on my desktop — it gives me peace-of-mind). I would have included Google Reader, but she had already included it in her post.
If you have time, click on the Edublogger link and submit your own top three in a comment.